The invention is based on an electric drive unit for vehicle systems, such as power windows and windshield wipers.
A known electric drive unit for power windows in motor vehicles (German Utility Model DE 90 13 006 U1) has a gear housing, adjoining the end toward the commutator of the commutator motor. The commutator motor has a lengthened motor shaft, in the form of a gear drive shaft (worm shaft) which protrudes into the gear housing. A printed circuit board electrically connected to an external connecting plug and commutator brushes and to components of an electronic system for the motor is disposed in an electronics housing. The printed circuit board has a one-piece receiving part for the brush mount and a one-piece receiving part for the connecting plug. The electrical terminals of the components, brushes and connecting plug are bonded, to make electrical contact, to the conductor tracks of the printed circuit board. The brushes are disposed diametrically on the commutator and are each retained radially displaceably in a quiver formed in the brush mount. The electronics housing is a component of the gear housing and is closed by an electronics housing cap that is integral with the gear housing cap.
From German Patent Disclosure DE 44 30 798 A1, a lead frame is known that is made of metal strips that serve as conductor tracks for connecting electrical components. The electrical components are mounted on the lead frame, and their terminal leads are welded or soldered to the lead frame. As an example of possible components, integrated circuits, sensors, resistors, capacitors, and so forth can be used. The lead frame with components mounted on the lead frame is spray-coated with plastic.
The electric drive unit for vehicle systems has an advantage that all the electrical components and current-carrying connections are concentrated on a lead frame that is standardized for each motor type, that assures good handling, and that has defined interfaces with the basic plug. The commutator brushes, embodied as hammerhead brushes, are an integral component of the lead frame and need not be mounted and wired separately. The expense of assembling and installing the brushes is dispensed with. At the same time, the carrier plates of the hammerhead brushes furnish the brush contact pressure forces on the commutator. The delivery of the carbon brush is done from the back side of the carrier plates, facing away from the commutator. The unit part formed by the lead frame with components and commutator brushes can be automatically manufactured, easily assembled automatically welded, and easily installed.